A Lesbian German nationalist that lives in Switzerland, married to an immigrant, and has adopted children.
A complete contradiction to everything the AfD believes in.
My head hurts even trying to make any of that make sense. So I'm going to just assume the party doesn't actually have any genuine convictions, entirely performative hollow people. Anything to sit in the big chairs.
I once thought that I had some understanding of Germans' political thinking, however that was over thirty years ago when my daily news consumption (both TV and print) included local German language outlets (plus of course regular INTSUMs). But, back then, those demographic variables would have precluded much of eastern Germany (even after the wall came down) and failed to account for the regional differences among the Germans. Since I no longer follow "local" German politics or events, my understanding (or interest) has also deteriorated.
Just as we have stereotypical images of Canadians' political/cultural/societal leanings depending on the province/region they are from (or of our American neighbours), so too, are the Germans. The broad strokes of their political divides are much like Canada's; East-West, North-South (though they don't have the wide, uneven population split), urban-rural and of course the differences from state to state.
As to your difficulty in understanding how Frau Weidel can co-lead AfD, I suggest there could be a comparison with a Canadian politician though it is likely that the underlaying social and political beliefs of each may differ. I refer to the Premier of Alberta, Danielle Smith. I have in the past given my opinion that I believe Ms. Smith to be a political opportunist, encouraging and accepting support from the extreme elements of the Alberta conservative movement. It would not surprise me if she did not personally hold those views as long as she (personally) gains and remains in power even if that means risking the breakup of the country.
I believe Frau Weidel to also be a political opportunist. When she started her political career, AfD was a relatively moderate (though conservative) Euroskeptic group focused on economic policy rather than cultural issues/nationalism. That started changing a few years later as mass immigration into Germany (and Europe as a whole) increased. AfD didn't form from the extreme right, they accepted the extreme elements into an already conservative group. Weidel may, or may not, subscribe to those extreme views, but I expect she will play along with them and use them for AfD to gain power.
When the newly elected Bundestag meets for the first time this week, far-right Weidel, who lives in Switzerland with her Sri Lankan-born wife, will lead its largest opposition party
www.theguardian.com
https://archive.ph/MOGLs (non-paywall)
As for what the AfD stands for
To go back to regional differences in German political preferences and how that played in SfD making great head way in the state that is the subject of the OP, this from DW may be of interest.
The AfD has emerged as the strongest party in Germany's eastern state of Saxony-Anhalt by a wide margin. What is driving support for the far right in this predominantly rural eastern German state?
www.dw.com